Half to moses g



(No Model.)

P. W. COLE.

ELECTRO MAGNET AND ARMATURB. No. 403,517. Patented May 2l, 1889.

N PETERS. PnomLixmgmpher. vfamiugwn, D. C.

UNITED STATES PATENT OEEIcE.

FREDERICK XV. COLE, OF NElVTON, MASSACHUSETTS, ASSIGNOR OF ONE- HALF TO MOSES G. CRANE, OF SAME PLACE.

ELECTRO-MAGNET AND ARMATURE.

SPECIFICATION forming part Of Letters Patent N0. 403,517, dated. May 21, 1889.

4 Application filed May 24, 1888. Serial No. 274,950, (No modeld To all whomI t muy concern-s Be it known that I, FREDERICK W COLE, of Newton, county of Middlesex, State of Massachusetts, have invented an Improvement in Electrolagnets and Armatures, of which the following description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts.

The object of my invention is to produce an electro-magnet and armature, which latter may be strongly attracted through a long range of movement, thus giving a powerful movement to the armature through a large angle upon its pivot, so that it may be used for many purposes where a mechanical operation involving some considerable expendif ture of power is produced by an electric current, lt is impracticable to perform such operations by electro-magnets of moderate sizes of the usual construction, owing to the fact that the attractive power diminishes rapidly as the distance of the armature from the poles increases, so that with an ordinary fiat-pole magnet and armature a movement of niuch extent cannot be efficiently produced.

The present invention is embodied in an electro-magnet of the usual horseshoe type,

having its two poles side by side and similarly shaped, combined with a pivoted armature and retractor therefor, said armature being pivoted on an axis parallel to the line joining the two poles, and the armature and polar extensions being so shaped thataportion of the armature moves laterally along or substanA tially parallel with a surface of the pole extension, so that the actual distance between the adjacent surface of the armature and polepiece is small in amount and varies but slightly in different positions of the armature, although the mass of said armature as a whole approaches the poles of said magnet under the attractive iniiuence thereof and is removed from said pole under the action of the retractor when said attractive iniiuence is ren moved. In addition to the portion of the armature that thus moves laterally by the surface of the polar extension. or through the magnet field, the armature may also have a portion which moves toward and from a corresponding surface of the magnet-poles in substantially the usual manner, thus giving the magnet increasing power while the armature approaches, as maybe desirable for certain uses to which the armature and magnet may be put.

Figure l is a side elevation of an electromagnet and armature embodying this invention; Fig. 2, a front elevation thereof; Fig. 3, a rear elevation of one of the pole-pieces shown in Fig. l, vand Fig. 4- a modification to be referred to.

The main body of the magnet, consisting of the cores a, upon which are wound the coils Z), of insulated wire, and the back strap, a', connecting the said cores, may be of usual character, the invention relating especially to the construction of the pole-pieces c and the armature (l cooperating therewith. The said polepieces c or enlarged extensions of the projecting ends of the cores are shown in this instance as having a fiat surface, c', inclined to the axis of the cores, and a curved surface, c2, which should be substantially concentric with the axis upon which the armature d has its pivotal movement for most purposes,

As shown in Figs. l. and 2, the said armature is pivoted at c directly upon the said poles, which are provided with lugs or hinge projections f to receive the pivot-pins, which pass through supporting-arms or brackets g attached to the armature d, the arms g being of brass or other non-magnetic material, so as not to close a magnetic circuit between the poles of the magnet.

The armature or part moved by it may '1uweighted, so as to be retracted by gravitv1 alone, as shown in FiO. 4, or a retractingspring may be provided, as shown at 72, Fig. l.

The armature c7, composed of a portion, d,whieh is preferably curved so as to be substantially concentric with the axis f, about which it moves, and parallel, or nearly, so with the surface c2 of the pole, so that in a movement of the armature toward and from the magnet-that is, between the full to the dotted line position-the armature moves along the side of the pole instead of moving toward and from it, as in magnets of usual construction.

By having the sides c c2 of the pole inclined to the axis of the core the magnetic strength IOO tracted, and when arranged with relation to the poles, as shown in Fig. 1, it is powerfully moved by the attraction of the magnet through an are of about forty five degrees with as great a power as an armature of usual construction pivoted in the usual manner is moved through a very small arc.

The relation of the mass of the curved portion d of the armature to the pole is such that when near the attracted position (shown in full lines, Fig. 1) the magnetic attraction operates with 'diminishing effect, as the portion of the pole near the extremity tends to draw the armature outward or toward its retracted position; but whenit is required to give the magnet increased power .upon the armature as the latter is drawn up this is accomplished by making the armature with another portion, d2, that approaches the inclined face c in substantially the same manner as an armature of usual construction. ln the retracted position the portion cl2 is practically out of the fieldof attraction, but the portion d is then close to the tip or strongest portion of the pole, and is thus acted upon powerfully, and as the portion d approaches the full-line position, Fig. 1, in which the tip of the pole has less tendency to draw the said portion d inward, the portion cl2 comes into the yfield and is strongly attracted, thus making the entire movement of the armature very powerful.

The specific shape shown in Fig. 1 is not essential, and the shape may be modified in order to give different relations to the power in different positions of the armature, a portion of which moves laterally through the magnetic field or alongside of instead of directly toward and from the corresponding surface of the pole, and, ifrequired, anotherportion of said armature moves toward and from its corresponding pole-surface in the usual manner if brought into the range of powerful attractions by the laterally-moving portion. These two portions of the armature make a channel, which receives the magnet-poles within it when the armature is attracted.

Fig. l represents a modification in which the armature is pivoted at a distance from the pole of the magnet, instead of being pivoted directly upon the said pole, as in Fig. 1; but the construction is substantially the same, and the armature and pole have the same portions cooperating in the same manner and indicated by the same reference-letters.

In the construction shown in Fig. 4 the armature has an eective movement through an angle of ninety degrees, and might be employed, for example, to turn a damper for the purpose of controlling a tire, the armature being connected directly with the damper-spindle.

Amagnet and armature of this kind is especially useful wherever it is desirable to actuate the part of an apparatus with a reciprocating angular movement of great range without intervening mechanism, being for such purposes far more effective than magnets of the solenoid construction,which are commonly employed where a rectilinear movement of long range is required. It is obvious that the long angular movement may be caused to produce a rectilinear movement by connecting mechanism, just as the long rectilinear movement of a solenoid may be made to produce an angular movement, and a magnet of the herein-described construction may be preferable in many cases where rectilinear movement of the actuated part is required.

I claim- 1. The combination,withan electro-magnet having a pole-piece with converging surfaces, of an armature composed of two portions, one of which is arranged' and moves substantially parallel with one of the surfaces of the polepiec'e, and the other of which portions approaches and recedes from the other surface of said pole-piece, substantially as described.

2. A horseshoe electro-magnet having two similar pole-pieces, each provided with pivotlugs at one side, combined with an armature pivotally connected with said lugs having two portions, one substantially radial to the pivotaXis and the other substantially concentric with said pivotal, axis, substantially as, and for the purpose described.

In testimony whereof l have signed my nam e to this specification in the presence of two subscribing witnesses.

FREDERICK W. COLE.

Witnesses Jos. P. LIVERMORE, M. E. HILL.

IOO 

